Pen



FIG. 1 is an upper front left perspective view a pen showing my new design;

FIG. 2 is an upper front left perspective view of the pen shown in FIG. 1, with the pen cap removed and placed on the opposite end of the pen for convenience;

FIG. 3 is a front elevation view of the pen shown in FIG. 1;

FIG. 4 is a rear elevation view thereof;

FIG. 5 is a left side elevation view thereof;

FIG. 6 is a right side elevation view thereof;

FIG. 7 is an enlarged top plan view thereof; and,

FIG. 8 is an enlarged bottom plan view thereof. 

CLAIM The ornamental design for a pen, as shown and described. 